1. Field of the Invention
The invention relates to a lever actuated looper throw-out device for a sewing machine employing one or more sewing needles and loopers. More particularly, the invention relates to a safety catch device that prevents improper operation of, and damage to, a sewing machine employing a looper throw-out device.
2. Background Information
Sewing machines employ one or more stitching needles and loopers, and an operator must often access the loopers for threading. To access the looper, the operator opens a cover on the sewing machine and disengages a looper holder from its sewing position by using a looper throw-out device.
A looper throw-out device, such as the one disclosed in U.S. Pat. No. 4,671,195, includes a release lever which disengages the looper holder. To thread the loopers, the sewing machine operator manually unlocks the release lever thereby and then pulls the looper holder out from under the sewing area. This provides the operator with the necessary space to thread the loopers. Once the operator is through threading the loopers, the operator must reengage the looper holder into the sewing position and then must lock the looper holder in place with the release lever. When the release lever is properly relocked, the looper holder is securely held in the sewing position.
At times, an operator will fail to lock the release lever before starting the sewing operation, and the sewing machine will be damaged by the unsecured looper holder or release lever. The looper throw-out device, the loopers and the stitching needles may be severely damaged. Moreover, the machine will tend to skip stitches and the thread will break.
This invention overcomes this problem by employing a device that prevents the operator from closing the cover of the sewing machine if the looper holder has not been secured in place by interlocking with the release lever. When the cover cannot be closed, this serves as a signal to the operator that the release lever of the looper throw-out has not been properly locked.